Detection of suspended matter in gases



l W. K|DDE ET .AL

DETECTION 0F SUSPENDED MATTER IN,GAsEs Fired une ze 1921 4 sheets-sheets' Tube ,V0.1 Tube Nov, 25, 1924.

v .l y w. KIDDE ET A1.

\.DE' IECTIQN OF SUSPENDED MATTER IN GASES Filed Juney 2,8.

1321 4 sheets-sheet 4' atented Nov. 25, 1924.

UNITED STATES IAliliNT oFF1cE.

WALTER HIYDE, 0F MONTCLAJIB., AND IBARZILL'AI GL WOBTH,'OF WESTOBANGE,NEW

JERSEY, JERSEY.

ASSIGNOBS TO KIDDE & rC0MPANY,".A GORPOBALTIQN 0F NEW DETECTION 0FSUSPENDED MATTER IN GASES;l

application nieuwe as, 1921. serial no, 480,967.

nue, West Orange, N. J.), have jointly invented certain new and usefulImproverrients in Detection of Suspended Matter 1n ases Our inventionherein described has fory its, object the detection and observation ofsuspended matter in air or other gases. is` particularly applicablertothe detection lof very minute uantities of Smoke in air,

but is equally e ective in the detection of suspended dust particles,partially condensed vapors and other forms of suspended matter, thedetection and observation of which may be desirable in various arts. A.specific embodiment of the invention relates to the detection yof smokein apparatus for indicating and extinguishing fires in vessels orbuildings, and particularly of the type vdisclosed in Patent No.1,343,911, .June 22, 1920, wherein a pipe leads from each of severalcompartments of the vessel to an.

indicating cabinet whereby a fir'e originating in any compartment willbetray its presence by smoke issuing from the mouth of the correspondingpipe in the indicatin cabinet, and can thereupon be extinguishe by'directing a fire extinguishing gas` or vapor through said pipe.' tJ isobvious that the detection of a lire' should be made as speedily aspossible after its inception, and itis therefore important that thepresence `of smoke in the indicating cabinet should be observed evenwhen' it exists in very minute quantities.` To permit a lire tov smolderuntil relatively large amounts of' smoke are produced obviouslyincreases .the time required toextinguish the same. By our presentinvention we are able to detect with entire certainty the presence of ismoke man times less in amount than could be posslbly observed by itsissuance int'oi a generally light cabinet fromthe mouths ofy thedetectorpipes asdisclosed in ourpatent above referred to. i

Broadly stated our invention consists 1n 4 ew. Jerseyy (post-oliiceaddressNo. 422 Gregory Aveleading the smoke, vapor or other finelysuspended `matter into a chamber from which general illumination isexcluded and utilizing alight beam so directed as to be substantiallyinvisible, the finely suspended `matter being caused toA progress.through the beam whereby the particles will become villuminated byreflection, and their presence thus manifested. Our invention as thusbroadly defined may be carried out in many different ways, some of whichare illustrated in the accom anying drawings forming part of this specication and lto which attention is now directed.

In the drawings:

Fig. vhows more or less diagrammatic- It ally the constituent parts of alire indicating and extinguishing system ofthe type dis.

closed in our patent referred to, illustrating a convenient arrangementfor detectin the presence` of vsmoke luing from any o the detectorpipes.

Fig. 2, an enlarged view partly iny section of the kdetecting deviceshown in Fig. 1.

Fig. 3; a diagrammatic view illustrating the possibility of using twosources of i1- lumination withk a large number of detector pipes. n

Fig. 4, a modification showing a single source of illumination with aplurality of r`detector pipes, the smoke passing transversely throughthe light beam.

Fig. 5, shows lan alternative arrangement in which the lightbeamisprojected.k downward into a tube; and

Fig. 6, an alternative form ,of observation ltube in which'theobservationy is effected throu h thek transparent wall of acontinuousftu Inall of the above views corresponding parts arerepresented by the same` numerals.

In apparatusheretofore used for detecting smoke'or other su ended matterissuing from an orifice, it has een usual to observe the issuing jet bylsimple unaided vision, the smoke being seen in the general illuminationof daylight or otherdiused general illurmnation.v This is leffectivewhen the smoke or suspended ymatter is suiiicienfv from'fa *concealedsource and observing the illuminated particles from a "direction obliqueto: that of the beam. When the gasior vapor is freev from suspendedmatter,

but if suspende matter exists even in vminute quantities theparticles-'cause difof which detector pipeslead to an indicafraction orreflection of the light which thus becomes visible as a -`continuous and'pr longed beam. -In the preferred formgof the apparatus where the lightis projected Athrough ythe, Atube from which the particle- 'be'aringgasor vapor issues, from' a source or vmirror .inV the`.axis of fthe tube,the

vslightest trace of! suspended matterrv will cause anl appearance asoffa glowing coal in themouth of the tube, witha'shaftv'of light"projecting from it. This not only in- 'I creases enormously thedetectingv sensitivit of the apparatus, but produces a visual e -fectysostriking as Jtov arrestA attention at once', being thus highlyeiicientfas fa': tire alarm.-y Byvmeans of this invention, smoke orother suspended matter is rendered clear? ly` Visible whenso highlyVattenuated that itcannotv be detected byv ordinary observation; f'

1 Referring rst to' Fig. 1, a pipel is shown n leadingfrom the valve'cabinet 2 to a com- 30 l j vided with a hood 4 located preferabl near'partment`3, the eiid of the pipe'beig prothe top of the compartment. It'will e understood of course that Aas many of these pipes l are employedas may 'be needed to reach -the several compartments ofthe ship or otherstructure with which the'apparatus is used. Each pipe is provided with avalve 5 which `may' be opened to permit steam or other extinguishingmedium to pass from the header 6 to which the steam pipe 7 leads, withkmain valve V8 therein. Ifvdesired, carbon-dioxide or other re eX-ti'nguishingirgaspmay be admitted to the lligadr 6 from the gas tank 9throughvalves 1 Leading from each ofthe extinguishing pipesyl is adetector orv smoke pipe 11, all

tor cabinet 12y having a transparent Vfront `13. Each detector pipe` isprovided with a valve 14 'which is norm-all opened, "and each valve isprovided with'av ever 15 extending down" over the hand-wheel of thecorre'- sponding steam valve,.so that before the steam valve can `beopened'the corresponding smoke valve. 14 must be `first closed tolprevent steam` from entering the detector' pipe. This specialarrangement of interlocking ,valves is not claimedy herein, but is madekthe Subject. of a separate application Serial No.l (180,966 filed b uson even date herewith.iy Suction; wit in thefdetectolPipes is created bya fan 16 as shown, whereby a vcirculation will be maintained from theseveral compartments, and any erably at an angle. as shown, and theobservation tube bein located in the bottom of the indicator lca inetwhereby the gas or vapor with its suspended matter will be drawnoutthrou'gh the mouth ofthe obser- `vation tube. Coaxial with theobservation 'tube 17 is asourceof light 18 which'may be lan incandescentlamp located ydirectly `in the axis as shown in Fig. 6,' or a mirror orlprism 19 l and 2.

InfFig. 2, we .show observatlon tube No.

in the axis yasrshown` in Figs.

l2 as receiving light directly from the lamp 18, andthe other tubesequipped with mirrors so that the light from the same lamp is reflected"axiallyfthrough the tube. Light is thus caused to pass through the tubein the same direction as the current of gas or vapor, forming a beam inwhich the suspended matter is strongly illuminated. As an alternativethe light may be projected ina direction opposite to the gas flow asinFig. 5. 'n Preferably the beam is concentrated by a lens 20 orequivalentmeans.

`Thev 'orifice or observing portion of the. )tube :is so llocated thatthe observer views -it from a position out ofthe lpath ofthe beam orbeams, that is, from anangle'oblique to the beam orv beams, as indicatedin Fig. l, so that the light is completely invisible when the gas isclear and clean, but any suspended matter acts as a secondary source oflightand appears as an illuminated shaft of strikingvisibility. Y

In the simple arrangement of F ig. 2 Vthe source of light 18. is shownas an incandescent lamp. The lens 20fis shown as va convex lens mountedin the axisof the robservation -tube 1 7 or. in an offset, andprojecting a concentrated 'beam of'light through the orifice or' mouthof the tube. We prefer to employ a lens having a relatively largeaperture with relation toits focallength so as to utilize asy large acone of light as possible pointv a short distance above theforifice Yofthe observation tube' as indicated in Figsr. 2, 5 and' 6, the point offocus` beingv shown in directiline with the observers eye when placed ata convenient ypoint out of -the path of the beam. Thisy arrangementresults in a highly effective illumination.

Instead lof projecting 4the beam of light on the gas orvaporissuing'from the orifice froma point within the orifice, theprocess may be reversed, a light beam being projected toward the `t-ubefrom the outside as from the lamp18, and the distance of-jthe lamp fromthe lensvis preferably so chosen' asto focus an 'image'of the filamentat a shown in Fig. 5.v lThe source of light, 18 is'. shown vprojecting abeam through a convex v lens 20 to a focal point located a shortdistance from the orifice of the indicator tube 17. In this case theentire tube constitutes the gas or vapor channel, the branch 11 beingomitted, and the light entering the tube from the source above isabsorbed without producing a glare visible to the observer.

For the sake of simplicity of construction, we prefer to locate thetubes approximately in a circle or circles with the source of light atthey center. 'This arrangement has the advantage of permittting theoptical systems of'all the tubes in a given circle to be made identicalor substantially so. Such an arrangement of tubes is shown in plan,

view in Fi 3 where two sources of illumination X serve to illuminatealarge number of observation tubes arranged around the source ofillumination in substantially concentric circles. To prevent the cuttingoff ofthe light from the tubes in the outer cir'clesthe tubes may bearranged either between those in the inner circle ,or in differentuertical planes, Las shown in F ig. 2, the angle of the'mirrors beingproperly selected to project the light beam axially throu h theobservation tube.

We prefer to emp oy a clear glassy window 2l at the lower opening of theobservation tubes, as shown in Fig. 2 (see tubes Nos. 2 and 3, Fig. 2),in order to protect the optical surfaces of the lens 2O and mirror 19from dust. Instead of this arrangement the lens itself may be located atthis point. (see tube No. 1, Fig. 2), in which case the clear glasstakes `the place of the lens. above the mirror. Thus all opticalsurfaces are protected except those that are readily accessible forcleaning. Each observation tube is made of two sections, as shown inFig. 2, telescoping together as with common optical instruments andclamped in position by a lgrip ring 22, thus permitting both verticaland angular adjustment and allowing also the lower section of any tubeto be removed for the purpose of cleaning the same.

While we prefer to employ an observation tube terminatin in an openmouth or orifice as described, this is not necessary and sometimes, asin the case of noxious gases, not desirable. For example the tube may becontinuous and its observation portion 23 made of glass or othertransparent materiak as in 'F ig. 6. In this case care should be takento prevent the beam of light from striking the glass and thus producinga visible illumination. This may be done by restricting the diameter ofthe tube at the` point 24, as shown.

, Another alternative arrangement is shown in Fig. 4. Here the lightbeam is not axial with the tube as in the preferred fornabut visprojected horizontally above a row of it impinges upon suspended matterissuing-l from the orifice of one of the observation tubes. With thismodification of the invention, two plano-convex lens y27 are employed toform a parallel light beam which projects across the mouths of theobservation tube.

The. operation of the device has been al- `ready generally indicated.Normally the steam valves 5 are closed and the valves 14 opened so thatthe suction fan 16 will cause a circulation of air from within` all thecompartments or rooms of a, ship or buildf ingor other structure to beprotected. Preferably a perforated plate 28 is mounted near the top ofthe observation cabinet 12, .so as to secure a uniform suction over thewhole area lof this, cabinet, whereby the smoke issuing` from theorifice of the observation tubes will be drawn directly upward followingthe path ofthe light beams and not deflected by eddies. Obviously anyother form of exhaust which produces a substantially uniform flow ofairor gas may be employed. A canopy or screen 29 prevents the Vobserverfrom seeing the upper blackened portion of the indicator cabinet inAwhich the light is absorbed without producing a distracting glare. lncase fire occurs in any of the compartments, its presence will beindicated by smoke passing up through the detector pipe Vand throughlthe corresponding observation tube. By reason of the illuminating devicedescribed, vthis smoke even when extremely attenuated will be readilyand strikingly indicated. The observer, noting the orifice from whichthe smoke passes and thus locating the compartment in which fire hasoccurred, will thereupon proceed to close the valve 14 of thecorresponding detector pipe and open the steam valve`5 thereof, wherebysteam will be allowed to enter the compartment and thus extinguish theiiire. VWhen the valve cabinet 2 1s located at aj: distance from thedetector cabinet, for instance, at or near the engine room, the properinstructions as to location of the fire will be given by telephone orotherwise. v

It will be readily understood that the means for observing suspendedmatter here set forth is applicable not only to the detection of smoke,but it may be used also fora variety of other purposes.I Among thepossible. .applications of the invention may be mentionedthevobservation of flue gases from furnacesfor detecting suspended solidmatter due to incomplete composition, the

ag now described our invention, what We claim as new therein and desireto secure by Letters Patent 1s asfollows:

1. The -method of bserving suspended matter in a gas or vapor, whichconsists in causing a stream of as or vapor to flow into the path of aliglgit beam normally invisible to the observer, and observing theilluminated suspended matter from a point out of the path of the lightbeam, substantially as set forth.v

2. The ,method of observing suspended vmatter in a'gas or vapor,'vvhichconsists in causing a restricted stream of gas or vapor` to flow in'contact with a light beam ,normally invisible to the observer, andobserving the illuminated suspended matter' from a point out of the pathof the light beam.

3. The method of observing suspended matter in a gas or vapor whichconsists in'4 causing a stream of gas to flow through a tube,illuminating the gasor vapor stream 4by a light. beam normally invisibleto the observer, and observing the illuminated suspended matter from apoint out of the path of the light beam, substantially as set forth.

4.' 4The method of observing suspended matter in a vgas or vapor, whichconsists ink causing a stream of gas orV .vapor to flow parallel with alight beam and observing the illuminatedy suspended matter from a pointout of the path of the beam, substantially as set forth. Y

5. The method of yobserving suspended ymatter in a gas or vapor, whichconsists kin causing ap'stream of gas or vapor to fiow parallel with alight beam normally invisible to thel observer, and observing the streamfrom a point Where it becomes visible by diffraction 'o r' reection whensuspended matter is present, substantially as set forth. d. The methodof observing suspended matter in a gasl or vapor, which consists incausing a stream of gas or vapor to flow throu h a tube, illuminatingthe gas stream Y by a light beamalso traversingthe tube and observingthe illuminated suspendedmatter from a point out of thefpath of thebeam, substantially'as set forth.

7. llie method 0f observing suspended matter in a gas or vapor whichconsists in causing'the gas or vapor With its suspended matter to issuefrom an orifice, projecting a beam of light in line with .the stream ofgas and observing the illuminated matter from a point out of the path ofthe beam.

8. The method of observing suspended in a4 gas or Vapor, which consistsin causing the gas with its suspended matter to' issue from an orifice,projecting a beam- .of light through the orifice on the matter issuingthereon, and observing the illuminated matter from a point out of thepathl of the beam, substantially as set forth.

9. The method of observing suspended matter in agas or vapor whichconsists' in causing the gas or' vapor with its suspended mattei' toissue from an orifice, projecting suspended matter to pass through atube, 1

projecting a lconcentrated axial beam off light through they tube from asource ex ternal tothe tube,y and yobserving the illuminated matter froman an le oblique to the vvaxis, substantially as set orth.

11. The method of observing suspended sists in causing the gas andsuspended matter to issue from an orifice, projecting solid matter in agas or vapor, which conthrough the orifice a beam of light normallyvinvisible to the observer,- but becoming Visible by diffraction orreflectioniwhensuspended solid matter is present, substantially as setforth.

12. Apparatus for detecting suspended matterin gases, in which arecombined an observation tube, means for causing a current of gas withsuspended matter to flow through the tube, means for projecting a `beamof light through the tube parallelwith its axis, and means for observingthe illumif nated suspended matter froman angle ob-fl lique to the axis,substantially as set forth.

13. An apparatus for detecting suspended matterin gases, in which arecombinedan observation orifice, means for passing a cur, rent of gas .orvapor with its sus ended l matter through the orifice, a source o light,

means for projecting a concentrated beamfrom said sourcethrough the gasor Vapor current, and means for observing the illumie nated suspendedmatter from a point out of the path of the beam, substantially as setforth.

14.-. An apparatus for detecting suspended vmatter in gases or vapors,in which are combined an observation orifice, means for passing acurrent of gas of vapor with its suspended matter through the orifice',a source of light, means for rojecting a concentrated beam from said)source axially with respect to the gas or vapor current, and `means forobserving the illuminated lsuspended matter froma point', outfjof thepath of the beam.

15. An apparatus for detecting suspended matter in gases or vapors, inwhich are com-r bined an' observation orifice, means for passing acurrent of gas or vapor withits suspended matter through the orifice, asource of light, means for projecting a concentratled beam from saidsource through said orifice, and means for observing the illuminatedsuspended matter from a point out of the path of the beam, substantiallyas set fort f 16. An apparatus for detectingy suspended matter in gasesor vapors, in which are combined an observation orifice, means forcausing a current of gas or vapor with suspended matter to issue fromsaid orifice, a source of light located out of the axis of the orifice,and a mirror located in said axis and projecting an axial beam from saidsource through the orifice, substanitally as set forth.

17. An apparatus for detecting suspended matter in gases or vapors, inwhich are com bined an observation orifice, means for causing a currentYof gas or vapor with `suspended matter to issue from said orifice, asource of light located out f the axis of `the orifice, a mirror locatedin said axis and projecting an axial beam from said source through theorifice, and a lens for concentrating said beam, substantially as setforth.

18. An apparatus for detecting suspended matter in gases or vapors, inwhich are combined a plurality of observation orifices, means forpassing currents of gas or vapor with its suspended matter through saidorifices, a single source of light, means for projecting a concentratedbeam from said source with respect to the several orifices and incontact with the several gas or vapor currents, and means for observingthe illuminated suspended matter from a point out of the path of theseveral beams, substantially as set forth.

19. An apparatus for detecting suspended matter in gases, in which arecombined a plurality of observation orifices, means for passing currentsof gas or vapor with its suspended matter through said orifices, asingle source of light, means for projecting a cencentrated beam fromsaid source axially with respect to the several gas or'vapor currents,and means for observing the illuminated suspended matter from a pointout of the path of the beam, substantially as set forth. l

20. An apparatus for detectin suspended matter in gases, in which arecom ined a plurality of observation orifices, means for passing acurrent of gas or vapor With its suspended matter through the severalorifices, a source of light, means for projecting a concentrated beamfrom'said source through each of the several orifices, and means forobserving the illuminated suspended matter from a point out of the pathsof the beams, substantially as set forth.

21. An apparatus for detecting suspended matter, in which are combined aplurality of observation orifices arranged substantially circularly, asingle source of light located centrally with respect to the severalorifices, means for passing a current of gas or vapor with its suspendedmatter through sev-` eral orifices, means for projecting a concentratedbeam from a" single source axially `through each orifice, and means forobserving .the illuminated suspended matter from apolnt out of the pathof thebeam, substantially as set forth.

23. An apparatus for detecting suspended matter in gases, in which arecombined a plurality of observation orifices arranged ap,

proximately in concentric circles, a single source of light centrallylocated with respect to ysaid orifices, means for passing a current ofgas or vaporwith its suspended matter through the several orifices,means for projectmg a concentrated beam from said source axially withrespect to the several orifices, and means for observing the illuminatedsuspended matter from a point out of the paths of the beams`substantially as set forth.

24. An apparatus for detecting suspended matter in ases or vapors, inwhich are combined a p urality of observation orifices locatedapproximately in concentric circles, a single source of light centrallylocated with respect to said orifices, means for passing a current ofgas with its suspended matter through the several orifices, means forprojecting a concentrated beam from the single source through theseveral orifices, and means for observing the illuminated suspendedmatter from a point out of the paths of the beams, substantiallyas setforth.

25. An apparatus for detecting suspendedY matter in gases, comprising incombination an observation cabinet, means yfor exhausting air therefrom,a plurality of observation ori-v fices opening into said cabinet,connections for admitting gas or vapor with suspended matter to saidorifices whereby currents of gas or vapor will flow therefrom, means forprojecting light in contact with the gas 4or vapor currents, and meansfor observing the illuminated suspended matter from an angle l blique tothe axis, substantially as set ort 26. An apparatus for 'detectingsuspended matter in gases, comprising in combination an observationcabinet, means for exhausting air therefrom, a plurality of observationorifices leading into the cabinet, connections luminatedsuspended matterfrom. a point .for 'projectingV4 a concentrated light beam axially withrespect 1to each orifice, p and means for observing, ,the illuminated!suspended matter from apoint out of the paths of the beams,substantiallyas set forth. 4

27. An apparatus .for detecting suspendedl matter in gases, comprisingin combination an observation chamber, means Jfor exhausting airtherefrom,l aplurality of observation .orifices leading'ntosaid chamber,rmeans for admitting gas or vapor with rits suspended matter n to eachorifice, vwhereby a current of .gas or vaporwilly issue therefrom, meansJfor projecting a o concentrated light beam throughl each oriice,'andmeans 'for observingl the 11# out of the paths ofthe beams,substantially as set forth. l

28. apparatus for detecting suspended matter in gases, comprising invcombination an observation cabinet, means for exhausting air therefrom,connections for admitting gas orvapor with its suspended matter to eachorifice,l whereby currents of gas or vapor will issue therefrom, asingle source 1 29'. An apparatus for detecting suspended beam from'said source axi ly. with respect 30 to the s everai orifcespand meansffor obpservinglthe illuminatedv suspended matter t from apoint out; ofthe paths' of' the beams,

substantially asset forth.

matter in gases, comprising incombination van observation cabinet-.meansfor Aexhaust Ing a1r therefrom, Vaplurality of observation orificesleading into ysaid cabinet, connections for admitting gas or vapor withits suspended matter to saidforicesrwhereby currents of'gas orf'vaporwill issue therefrom,a sin-A gle source of. light, means for .projectinga concentrated beam from said source, .through eachyof the severalorifices, and means for "observing the illuminatedgsuspended matter,,from a point outyof the paths ofthebeam's, substantially as lse, Thisspecification signed and witnessed this 24 da57 of June, 1921.

a y ,'WA'LTER KIlDE.

` Witnesses:

FREDERicK 'Si F-ITsWoRTH. G. A. Hownr."y Y' BARZILLAI G. WORTHA

